Stop both WDS Services
Copy your RemoteInstall directory. By default its located C:RemoteInstall (REMINST) unless you changed your directory.
Navigate to your new server where your will be copying the files to.
Quick tip: You can navigate to your servers C: from your old server. Open up a run command or in explorer adddress bar and type \servernameC$
Paste the directory into the new servers RemoteInstall directory.
Start WDS and all your images, drivers, etc should be there!